Application of aerated biofilters for production of high quality water for industrial reuse in West Basin

The results of 5 years operation of 8 full-scale up-flow aerated Biofor^® biofilters, installed at the West Basin Recycling Plant treatment plant (California), demonstrated the efficiency and reliability of this technology in the production of high quality ammonia free water for industrial reuse as cooling water in oil refineries. High nitrification rates up to 0.75 kg d⁻¹ m⁻³ (0.047 lb d⁻¹ ft⁻³) were obtained atwater velocities of 6.7 m h⁻¹ (867.5 gpm). The hydraulic retention time in the biofilters was short without any negative consequences on the process. During all five years of operation, all Biofor^® units demonstrated very reliable performances with 100% ammonia removal efficiency and very low residual suspended solids concentration of about 4.0 mg TSS L⁻¹.